Why Ed Miliband may outdo David

'Ed Miliband will never be prime minister. You know it, I know it," wrote Matthew D'Ancona in the Telegraph. The reason? "David offers his party years and years of work." Ed in contrast merely offers "a big smile and a hug". Many think the same way. David Blunkett thinks David by far the better candidate because he has "the experience and grasp of global challenges". Despite Ed's surge in the polls, many still argue that David's five years of cabinet experience qualify him for the job and that he will make a far more formidable leader and threat to the Conservatives because of it.

But is experience essential for a party leader and prime minister? Some of Britain's most successful premiers had run one of the top three offices – the Treasury, the Foreign Office and the Home Office – such as William Gladstone and Winston Churchill. But experience is no guarantee of success. James Callaghan held all three posts before he became PM but left little mark and badly misjudged arguably his biggest decision, the timing of the general election. Margaret Thatcher succeeded him in 1979 with little cabinet experience, but few doubted her power, for better or worse. Many unsuccessful leaders had considerable experience, including Anthony Eden who had spent 10 years as foreign secretary and Ted Heath who became prime minister in 1970 after a succession of senior posts.

Tony Blair came to power with, as he reminds us on the cover of his memoirs, experience of no other government department, yet he became Labour's most successful leader in electoral terms. David Cameron entered No 10 with no ministerial experience, nor other leadership experience. Yet in his early months at least, he has shown himself to have the gravitas of a leader.

In the US, some of the successful presidents have had little executive experience. In 1960 Kennedy beat Nixon, who had spent eight years as Eisenhower's vice-president, and rapidly became a leader of international authority. In 1980 Reagan beat Carter, the incumbent, and became the president who won the cold war. In 2008 Obama, with experience only of the legislature, became president and has the potential to become one of America's great leaders.

It is not only in politics that too much is made of experience over promise. In business and sport, and even in running schools, some of the greatest leaders have either been late developers, or have revealed quality in office that was not seen in their ascent. Top leadership requires special gifts, of physical and mental strength, clarity of vision and moral courage. Too many leaders are merely gifted administrators. They lack the key ingredient that all great leaders need, and that is vision. Thatcher had it, Eden did not. Obama has it, George W Bush did not. Mandela had it, Zuma does not. Adenauer did, Schröder did not. It is the ability to see that we are at point X now, but we need to go to point Y. More than that, it is the ability to inspire and mobilise people to go to that place. The lack of this vision explains why Britain has only had comparatively few prime ministers who have made an enduring difference.

Labour's challenge is to find a visionary leader who adapts the party in the light of profound socioeconomic change, to ensure social justice while maintaining Britain's competitive advantage. In the case of all five candidates, their previous experience of government or lack of it will count for little.

Ultimately it is only when a leader steps into the top job that it is clear how they will perform, whether it be the England cricket captain, the chief executive of British Airways or the leader of the Labour party. Most of all, the individuals will not themselves know. David and Ed, along with Andy, Ed and Diane, may all in their dreams imagine themselves outside the famous black door of No 10, or addressing the Labour party conference as leader. But the journey from dreams to reality is a journey ultimately into the unknown.

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